This conference, entitled "Differentiation of Normal and Neoplastic Cells" was held May 1 through May 4, 1985 at Kongresshaus Stadhalle, Heidelberg, Federal Republic of Germany. The advisory board of the International Society of Differentiation is responsible overall for the activities of the organization. The organizing committee is composed of Professor Werner W. Franke, Director of Institute of Cell and Tumor Biology, German Cancer Research Center, Heidelberg, President of European Cell Biology Organization (ECBO), and Vice-President of International Society of Differentiation (ISD); and Professor Melitta Schachner, formerly Assistant Professor of Neuropathology (1974-1977) at Harvard Medical School, and currently Professor of Neurobiology and Department Chairman (1977-present) at University of Heidelberg. Professor G. Barry Pierce, President of ISD, is an ex-officio member of the organizing committee and is responsible for the financing of the North American scientists. He is Chairman of Board of Scientific Counselors, Division of Cancer Etiology, National Cancer Institute, and a Lifetime Professor of American Cancer Society. (T)